Comparison of the Effects of Dexmedetomidine vs. Ketamine in Cardiac Ischemia/Reperfusion Injury in Rats - Preliminary Study.

OBJECTIVES: Following ischemia/reperfusion injury, antioxidant defense mechanisms may remain insufficient depending on the duration of ischemia which is caused by any reason (MI, after percutaneous coronary intervention, during cardiac surgery). After that, free oxygen radicals increasing within the cell cause structural deterioration. Cytokines which activate a series of reactions that cause tissue damage and inflammatory response are released during reperfusion of ischemic tissues. In this study, we aimed to compare the effects of dexmedetomidine and ketamine in cardiac ischemia/reperfusion injury. MATERIAL AND METHODS: The study included 18 rats randomly divided into three groups. Group I/R (n = 6): control, Group I/R-K (n = 6): ketamine, and Group I/R-D (n = 6): dexmedetomidine. Before the 10 min surgery, after the 20 min ischemia and 20 min reperfusion period, hemodynamic parameters were compared among the three groups. After the 45 min ischemia and 120 min reperfusion period, tissue samples were obtained from the rat hearts, and MDA, SOD, GSH-Px, IL-1ß and TNF-α levels were compared. RESULTS: MDA and GSH-Px levels were significantly higher in the control group compared to the ketamine and dexmedetomidine groups. However, both levels were similar in the ketamine and dexmedetomidine groups. SOD levels were significantly lower in the ketamine and dexmedetomidine groups compared to the control group, but they were similar in the ketamine and dexmedetomidine groups. IL-1ß levels were similar in all groups. TNF-α levels were significantly lower in the ketamine and dexmedetomidine groups compared to the control group. They were similar in the ketamine and dexmedetomidine groups. CONCLUSIONS: According to our study, it can be concluded that dexmedetomidine and ketamine have similar effects on reducing myocardial ischemia reperfusion injury. Dexmedetomidine provides better heart rate control but causes hypotension, so, because of cardiac depression, we think that its clinical use may necessitate further investigation.

Clinical features of aviators with coronary artery disease diagnosed by multislice CT angiography.

OBJECTIVE: Coronary artery disease (CAD) is one of the most incapacitating causes at military or civilian aviation. Aircrew population is crowding in number in our country. We aimed to identify the clinical features that could predict CAD in aircrew. METHODS: We retrospectively analyzed medical recordings of 26 aircrew (age 43.57±5.2) whose CAD was diagnosed via multislice computerized tomography angiography (MSCT). Clinical features, coronary risk factors and ST segment and T wave changes on resting ECG and treadmill test (TT), and laboratory findings of aircrew were recorded. RESULTS: ST depression <0.05 mV and minimally inversion (<0.03 mV) of T wave were found on 53.8% and 23.1% of resting ECG, respectively. 53.8% of patients had the family history of CAD. 73.1% of subjects were overweight. Family history was correlated with CAD and its type (p=0.023). 76.9% and 23.1% of the subjects had equivocal and positive result on TT, respectively. Presence of hypertension, hyperlipidemia, and smoking were lower and diabetes was absent. Additionally, subjects with two or more vessel disease were observed slightly older compared to those with one vessel disease (45.5±3.8 vs. 42.2±5.5, p=0.101). CONCLUSION: Aircrew ≥40 years old, with family history, ST/T changes on resting ECG, and equivocal results on TT even in the absence of multiple coronary risk factors may need further cardiovascular tests. MSCT is an effective and noninvasive way of detection of CAD in aircrew when needed.